niZmo -- I'm running SR16 cams (looks like you are also) and am switching the intake at 4400 and the exhaust at 4700. This gives me a perfectly smooth power curve -- looking at the dyno chart you cannot even see the switch points. Engines respond differently, so you should dyno yours to find your best switch points, and then check again if you change your intake, header, exhaust, etc. It makes a difference.